Implicit constructor call

[Marcin Kuszczak]

Chris Nicholson-Sauls wrote:

> LeoD wrote:
>> Hi,
>> can constructors be called implicit in D? Example:
> 
> You can get this using typesafe variadic arguments:
> # class Foo {
> #   this (int i) { }
> # }
> #
> # void test (Foo f ...) { }
> #
> # int main () {
> #   test(100);
> #   return 0;
> # }
> 
> See: http://digitalmars.com/d/function.html
> Heading: Variadic Functions
> Subheading: Typesafe Variadic Functions
> 

Interesting. I didn't know that. Could be useful, but to say true I think
that syntax/semantic is really strange... 


>> 
>> And why are there no templated constructors in D? Example:
>> 

> 
> Because constructors are not virtual... or at least that's the explanation
> given in
> compiler errors with this.  Seems more like just a special case.  I was
> actually a little bit disappointed myself, though the use cases seem to be
> pretty niche.

As I know constructors in C++ are also not virtual, but they can be
templated. I don't get connection here... 

It could be useful for variant classes which could be constructed with
different types. I couldn't translate Boost::Any well  because of that
problem (there is enhancement request on bugzilla).


-- 
Regards
Marcin Kuszczak (Aarti_pl)
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